TnAXSACTIONS OF SECTION D. 617 



except those studied by Leidy and Eisen in America, are at present almost entirely 

 unknown. Having lately had the opportunity of studying soino New Zealand 

 ' Limicolae,' through the kindness of Mr. W. W. Smith of Ashburton, I beg leave 

 to otler the following remarks upon them, and also upon some little known 

 British species. 



I have received from Mr. Smith numerous e.xnmples of Tuhife.r. Limnodrilus 

 and I'hreoryctes ; hence it appears that the general facies of the New Zealand 

 oligochajtous fauna is not widely diflerent from that of Europe. Indeed the two 

 former species seem to me to be identical with those which occur in this country. 

 With regard to Phreoryctes I have already ('Ann. and Mag. Nat. Hist.' 1888,) de- 

 scribed the principal facts in the anatomy of the New Zealand species ; since that 

 time a fresh consignment of specimens has arrived which enables me to add som& 

 details bearing upon its relations to other genera. 



Phreoryctes is one of those genera which break down the older distinction 

 between ihe ^ Oliyochteta terricolce ^ fini the ' Oliyoch(eta limicolm' ; and the New 

 Zealand species (which I have named P. Smithii) is more thoroughly intermediate 

 in its characters than either of the two European forms. It agrees with many earth- 

 worms in having paired seta;, two pairs of testes and of vasa deferentia without 

 atria ; but the characters of the seminal sacs, the eg^ sacs, and the ova (large with 

 abundant yolk) ally it to the lower Oligochreta. I land that the clitellum occupies 

 four segments (Nos. 10-13), and that there are no specially modified genital 8et» 

 present. A paper dealing with the general anatomy of this worm will shortly 

 appear in the ' Transactions' of the lloyal Society of Edinburgh. 



Another Oligochajt, which I have recently investigated, is the little-known form 

 yEolosotna. The following species are now known to occur in the British Islands : — 

 ^. quatei-narium (Ehrbg.), uE. Ehrenberyhii (Oersted), JE. varieyatum (Vejd.), 

 jE. tenehrarum (Vejd.), and .E. Headleyi (Beddard). The last two species I havt* 

 myself added to the British fauna, while some specimens of JE. varieyatum were 

 kindly sent to me by Professor Ilartog, from Cork. 



One peculiarity of this genus is the presence of coloured fatty globules in some 

 of the epidermic cells ; these globules are brownish-yellow in ^. quaternarium 

 and jE. Ehrenberyhii, greenish-yellow in yE. tenehrarum, bright-green in Ai. varie- 

 yatum, bright-green to bluish-green in yE. Headhyi. The pigment, which may be- 

 perhaps one of the ' lipochromes' of Krukenberg, is in every case changed to violet 

 by the action of alkalies. 



The sexual organs of the genus Bero have not yet been described, although, 

 thanks to the investigations of Perrier ('Arch, de Zool. Expt. I.,' 1872) and of 

 Boustield (' Journ. Linn. Soc.,' 1887), the general anatomy of this Annelid is well 

 known. These researche'', as well as others made previously, tend to prove that 

 Dero is a near ally of Nais. 



I find that the clitellum in the sexually mature worm occupies segments 5-7 

 (inclusive) ; there is no special modifica' ion of any of the setre in the neighbourhood 

 of the sexual orifices such as occurs in Xaix, but the ventral setae of segment G, on 

 to which the atria open, are entirely absent. 



There is a single pair of pyriform spermathecse opening close to the border line 

 between segments 4 and 5, the pouches themselves being in the latter segment. 



The atria, as already mentioned, open upon the Gtli segment ; the seminal sac is 

 large, and extends back as far as the 8th segment ; it is furnished with a pair of 

 contractile blood-vessels. 



The ripe ova, which are very few in number (2-4), occupy segments and 10. 



It will be obvious from the above description that there are no great ditl'erencea 

 between Dero and Nais in the sexual organs. 



8. Note on the Tarpon. By Professor McIntosh, M.D., F.E.S. 



A specimen, kindlj- sent by Lady Playfair, and measuring six feet in length, 

 was exhibited, and remarks made on its structure and habits. 



